1. Field of the Invention
The present invention relates to a method capable of easily manufacturing a semiconductor device in which a high-dielectric-constant film of a metal-insulator-metal (MIM) capacitor constituted of a high-k material having a dielectric constant of 10 or more is not formed in any of places where transistors or pieces of wiring are provided. The present invention also relates to a semiconductor device and a semiconductor device manufacturing method capable of preventing separation of a high-dielectric-constant film and an upper electrode of an MIM capacitor.
2. Background Art
Conventionally, in a case where a large-capacitance MIM capacitor is formed on a semiconductor substrate or in a case where an MIM capacitor is formed in a smaller area, a high-dielectric-constant film constituted of a high-k material having a dielectric constant of 10 or more, e.g., Ta2O5 is used as a dielectric film for the MIM capacitor (see, e.g., Patent Document 1 and 2).    [Patent Document 1] Japanese Laid-Open Patent Publication No. Hei 11-145387    [Patent Document 2] Japanese Laid-Open Patent Publication No. 2004-152796
A high-k material having a dielectric constant of 10 or more has high chemical stability in particular, and it is difficult to work by etching a high-dielectric-constant film constituted of such a high-k material. In the case of forming a dielectric film for an MIM capacitor from such a high-dielectric-constant film, therefore, it is difficult to remove the high-dielectric-constant film formed in a place where a transistor or a piece of wiring is formed. As a result, the parasitic capacitance of the transistor is increased or a wiring delay occurs.
Sputtering is applied to forming of a high-dielectric-constant film. The adhesion between a high-dielectric-constant film and a lower electrode of an MIM capacitor is weaker in the case of forming the high-dielectric-constant film by using sputtering than in the case of forming the high-dielectric-constant film by using chemical vapor deposition (CVD) with high reactivity at a growth surface. Thus, there has been a problem of such a high-dielectric-constant film being easily separable from a lower electrode. Further, an upper electrode of an MIM capacitor is separable more easily in the case of being formed on such a high-dielectric-constant film than in the case of being formed on a CVD insulating film ordinarily used as a dielectric film for MIM capacitors.